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Model Execution
Timing
Bring the model window to the front, before all other windows.
While the model is running, select File > Pause and Save/Save As.
Close the model.
When you open the model later, select Run > Continue Simulation to resume.
If you are doing this for debugging, do not re-save the model after continuing. Instead, repeat- edly run the model from its original paused state.
Timing
Unless you stop them earlier, all simulations run for a specified period of time. ExtendSim determines the duration of a simulation run based on the values entered in the Run > Simula- tion Setup > Setup tab; the duration is the period from the start time to the end time.
Continuous simulation timing
In continuous simulations, the duration is divided into intervals or steps of equal length, where start time is the first step and end time is the last step. The length of time, in time units, for each step is known as delta time or dt. The delta time determines how frequently model data is recalculated. For more information, see “Simulation timing” on page 88.
Discrete event simulation timing
In discrete event and discrete rate simulations, ExtendSim progresses from start time through end time by a series of events. Time progresses from one event to the next and the time between events is unlikely to be equal. The application calculates the time between events internally based on when an event occurs. The number of steps in a discrete event or discrete rate model is the number of events.
Simulation order (continuous models)
The Run > Simulation Setup > Continuous tab allows you to choose the order in which
ExtendSim executes block data for continuous models. The choices are Flow order (the default), Left to right, and Custom.
It would be unusual to change the simulation order from the default choice, Flow order.
Since this information pertains to running continuous models, it is discussed at “Simulation order” on page 92.
Time units
Time is the most common unit of measure in simulation. Each model has its own time unit that is managed in the Simulation Setup dialog.
How To